Generally, to supplement necessary nutrients such as glucose to a patient suffering from suppressed digestive functions, a liquid medicine stored in a Ringer bottle or the like is injected into a blood vessel of the patient. When it is necessary to inject a liquid medicine such as a special injection medicine, including an anti-cancer medicine or an antibiotic, to a patient or the like, the desired amount thereof should be injected consistently and continuously depending on a patient's condition. If the amount of special injection medicine necessary for a patient is not consistently and continuously injected, there is a risk of the occurrence of shock.
A device for injecting a Ringer's solution comprises a bottle (or pack) with a liquid medicine stored therein; a hose connected to a lower end of the bottle; a member for checking the flow rate of a liquid medicine, which is installed on the hose to enable the flow rate of the liquid medicine to be viewed by the naked eye; a syringe needle installed at a leading end of the hose to pierce a blood vessel of a patient; and a regulator installed between the flow rate checking member and the syringe needle to regulate the flow rate of the liquid medicine flowing toward a syringe by adjusting the cross section of the hose. In the liquid medicine injecting device constructed as above, a nurse pierces the syringe needle into the blood vessel of the patient and adjusts the regulator to regulate the amount of liquid medicine flowing to the hose, so that necessary nutrients can be supplied to the patient.
In a conventional regulator, the regulator is generally rotated upward or downward to change the cross section of the hose, thereby regulating the amount of liquid medicine flowing to the syringe needle. However, the conventional regulator has a problem in that it is difficult to finely regulate the flow rate of liquid medicine.